Visual control robot system

ABSTRACT

The visual sense control robot system has robot  1  driven three-dimensionally by an instruction from controller  11,  video cameras  2  for taking images of the all moving area of robot  1  from at least two directions, and control circuit  10  for giving the controller  11  an ordering signal to move robot  1  to the position of the visible target  3  as being taken image thereof by the video cameras  2.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a robot system controlling amoving position by visual recognition.

[0002] Nowadays, a number of robot systems have been employed inindustrial fields. In most of general purpose robot systems,pre-teaching assigns the operational positions of robot, which arestored in a control circuit. As the program goes on, the operationalposition is invoked, to which the robot is displaced.

[0003] In some other systems, the robot provided with a visual sensor isdisplaced to the direction and position of a target to be recognized bythe sensor. Even if a robot is provided with plural sensors, however,the limited size of robot does not allow to set the sensors away enoughfrom each other. This makes it difficult for the robot to recognize thecorrect three-dimensional position of the target. Such robot systems,which have not yet been universalized due to the restriction, stillremain costly.

SUMMARY OF THE INVENTION

[0004] The primary purpose of the present invention is to furnish avisual control robot system that allows for the operational control ofrobot by means of commercially available general purpose robots andgeneral purpose visual recognition devices also commercially available.

[0005] To achieve the purpose, a visual sense control robot system ofthe present invention comprises a robot means for movingthree-dimensionally, means for taking images all moving area of therobot, a visible target existing within the moving area of the robot, acontrol circuit having a function to recognize beforehand the movingarea of the robot and another function to store in a memory the positionof the visible target taken by said means for taking images as well asan ordering signal to move the robot to said position, and a drivecontrol means for driving the robot by said ordering signal from thememory of the control circuit.

[0006] A visual control robot system of another aspect according to thepresent invention for attaining the purpose further comprises to theforegoing control robot system, a display means and an input means forinstructing a coordinate on the display means connected to said controlcircuit further having a function to give said drive control means anordering signal to move the robot to a position corresponding to thecoordinate as instructed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 represents a block diagram showing the visual control robotsystem of the present invention.

[0008]FIG. 2 represents a flow chart of the operation by the controlcircuit of the visual control robot system.

DETAILED EXPLANATION OF THE INVENTION

[0009] The visual control robot system of the present invention hasrobot 1 that is three-dimensionally driven by the instruction from thecontroller 11, a video cameras 2 that are able to take images the allmoving area of the robot 1 from two directions at least, a visibletarget 3 existing within the moving area of the robot 1, and a controlcircuit 10 that recognizes beforehand the moving area of the robot 1 andgives the controller 11 the ordering signal to displace the robot 1 tothe position of the visible target 3 as photographed by the video camera2.

[0010] In the visual control robot system to which the present inventionapplies, connected to the control circuit are the display means 12 andthe input means 13 and/or 14 that indicates the coordinates of thedisplay means 12. This system may have a function to give the controller11 an ordering signal that displaces the robot 1 to the positioncorresponding to the coordinates indicated by the input means 13 and/or14.

[0011] Referring now to the drawings, a specific embodiment of thevisual control robot system applied the present invention, to which thescope thereof however is not to be limited, are described below:

[0012]FIG. 1 is a block diagram of an embodiment of the visual controlrobot system applied the present invention. As shown in FIG. 1, thereare three video cameras 2 x, 2 y and 2 z installed as visual field ofall moving area of robot 1 from the three directions. Connected to therobot 1 is the controller 11, which is linked with the control circuit,that is CPU, 10 through the intermediary of the input/output, that isI/O, interface 15. The three units of video cameras 2 x, 2 y and 2 z arelinked with the control circuit 10 through the intermediary of ananalog/digital converter, that is AND, 16. Connected to the controlcircuit 10 are a cathode-ray tube, that is CRT, display 12 as a displaymeans and a keyboard 13 and a mouse 14 as input means. Provided inaddition to these is a visible target 3 of which an image can be takenby video cameras 2 x, 2 y and 2 z. The visible target 3 has a built-inbattery and an infrared light emitting diode incorporated in itssurface. Target 3 has an adhesive portion so that it may stick to thesurface of an object.

[0013] The control circuit 10 has a function to recognize, as a movingrange, the coordinates where the robot has been displaced to the maximalextent, and another function to recognize the position of the visibletarget 3 from the video signal of the target 3 as photographed by thevideo cameras 2 x, 2 y and 2 z. Further, the control circuit 10 has afunction to give the controller 11 an ordering signal that displaces therobot 1 to the position corresponding to the visible target 3 andanother ordering signal that displaces the robot 1 to the positioncorresponding to the coordinates as indicated by the cathode ray tubedisplay 12 by means of a keyboard 13 and mouse 14.

[0014] In this embodiment, the cathode ray tube display 12, keyboard 13and mouse 14 have been loaded on a wheel chair.

[0015] The operation of the visual control robot system in the foregoingembodiment is described now referring to a flow chart in FIG. 2 asbelow:

[0016] The operation starts from Step 101, where control circuit 10perceives all moving area of robot 1. With the infrared light emittingdiode of visible target 3 kept on, the robot is made to hold the visibletarget 3 at a position within the moving area of the robot 1, that is,within the visual field area of the video cameras 2 x, 2 y and 2 z. Fromthe keyboard 13 or mouse 14, the coordinates of the moving area limit ofthe robot 1 are given to the control circuit 10, from which the orderingsignal displaces the robot 1 to its moving area limit by way of thecontroller 11. The image of the visible target 3 is taken by the videocameras 2 x, 2 y and 2 z, whose analog video signal is converted intodigital signal by the analog/digital converter 16 to be read into thecontrol circuit 10, where the total moving area of the robot 1 isrecognized, and the coordinates and ordering signal stored in the memoryarea.

[0017] In Step 102, visible target 3 is held by the robot 1 at a givenposition A within the moving area and the image thereof is taken by thevideo cameras 2 x, 2 y and 2 z with the position A computed and storedinto the control circuit 10 as an initial position of the robot 1. InStep 103, the first position the robot 1 is to be displaced to ismemorized in the control circuit 10. When to that effect the visibletarget 3 is put away from the robot 1 and installed at a position Bwithin the moving area of the robot 1, for instance, on a wheel chairwith a patient on (at position B which is not shown, Refer to thearrowed direction A B), the images of visible target 3 at the position Bis taken by the video cameras 2 x, 2 y and 2 z, whose video signal isread into the control circuit 10, and the position B of the visibletarget 3 is computed to be stored in the control circuit 10. Since theposition B of the visible target 3 at that time differs from the initialposition A of the robot 1, the control circuit 10 in Step 4 operates,from the memory of the storage device, the ordering signal thatdisplaces the robot 1 to the position B of the visible target 3 andgives this signal to the controller 11 through the input/outputinterface 15. The robot 1, which receives a control signal from thecontroller 11, displaces to the position B of the visible target 3,namely to the wheel chair.

[0018] Upon arrival of the robot 1 at the wheel chair by Step 5, thepatient on the chair point out another position C, where is a positionof second purpose such as a drug shelf, displayed on the cathode-raytube 12 by the keyboard 13 or mouse 14. Then the position enter into thecontrol circuit 10 as an interrupt signal. In Step 106, the orderingsignal is operated from the coordinates at C by means of the memorystored, and output at the controller 11 through the input/outputinterface 15. By the ordering signal from the controller 11, robot 1moves to the position C, that is to the drug shelf, and then where therobot 1 grasps a drug, as an essential task thereof. When the patientreleases the interrupt signal in the control circuit 10 from thekeyboard 13 by Step 107, the position B of the visible target 3 asphotographed by the video cameras 2 x, 2 y and 2 z differs from theposition C where the robot 1 holds the drug.

[0019] Since in Step 108, the control circuit 10 returns the robot 1 tothe position B of the visible target 3, the ordering signal is computedby the memory from the coordinate B being photographed, and given to thecontroller 11 through the input/output interface 15. By the controlsignal of the controller 11, the robot 1 will carry the drug to theposition B, that is, to the wheel chair.

[0020] Though three units of video cameras 2 x, 2 y and 2 z are providedin this embodiment, two minimal cameras will suffice. If two videocameras are taking images from visible target 3, since a video cameracan take a 2-dimension image under normal conditions, thethree-dimensional position thereof can be analyzed. However, in somecases where the visible target 3 enters in a shadow of an object, theimage thereof cannot often be taken a video camera if the system isprovided only with two video cameras. It is therefore desirable that atleast two video cameras out of three may take the visible target 3 atany position whatever the visible target 3 may be. Three video camerasat least are thus required.

[0021] As has been thus far described, an addition of a visualrecognition equipment to a robot enables to control the moving functionof the robot by means of the visual sense. The visual control robotsystem may thus be materialized at an extremely low cost. The visualsense control robot system according to the present invention may beused, for instance, in the care of patients.

What is claimed is:
 1. A visual sense control robot system comprising arobot means for moving three-dimensionally, means for taking images allmoving area of the robot, a visible target existing within the movingarea of the robot, a control circuit having a function to recognizebeforehand the moving area of the robot and another function to store ina memory the position of the visible target taken by said means fortaking images as well as an ordering signal to move the robot to saidposition, and a drive control means for driving the robot by saidordering signal from the memory of the control circuit.
 2. A visualsense control robot system as claimed in claim 1, further comprising adisplay means and an input means for instructing a coordinate on thedisplay means connected to said control circuit further having afunction to give said drive control means an ordering signal to move therobot to a position corresponding to the coordinate as instructed. 3.The visual sense control robot system as claimed in claim 1,characterized in that said means for taking images are an infrared videocamera and said visible target, which has an infrared light emittingdiode and a battery, is able to bond to a surface of an object and. 4.The visual sense control robot system as claimed in claim 2,characterized in that said means for taking images are an infrared videocamera and said visible target, which has an infrared light emittingdiode and a battery, is able to bond to a surface of an object and. 5.The visual sense control robot system as claimed in claim 2,characterized in that said display means and input means are loaded on awheel chair.